Don't ride after a rain. The trail will be muddy and damage will occur.
Like the name implies, the Meadow Loop is a more relaxing portion of the East Loop (Gruber's Loop). The singletrack is predominantly dirt, but it also travels through some grass. You'll want to avoid this trail during wet conditions. The trail is often wet and muddy for a week after decent rainfall. Instead, you can take the Old Shields Road Bed as a cutoff.